MX5Plus confirmed that the engine builder didn't need to do much work on them.
Eagle, K1 and Manley rods are the best of the budget rods - in hindsight I'd prefer Manley rods because they're "Manly".
FYI: The budget rods are slightly heavier than Carillo rods and they're only rated for ~600hp (which is about twice as much hp as an upper-eschelon modded MX5 can produce) vs the 1,000hp of Carillo rods (over 3 times as much) but they're also 40% of the cost of the Carillo rods so you can put those $$$ towards something else (eg. top-notch pistons)
I'm not a fan of the Autometer boost gauges.
The one I had many moons ago had a hard vacuum line that must feed into the rear of the gauge.
If that vacuum line gets a kink in it you will need to replace the vacuum line and get a new brass acorn to fasten it.
If you're the sort of guy that wants to mount it in a gauge pod and don't do many modz (ie. wont need to access it or the area around it again) it's probably not an issue.
I prefer gauges that separate the mechanical component and the electrical components of the gauge, you can mount the mechanical component anywhere that's convenient and out of the way and put the gauge anywhere, connecting them via an easily routeable wire.
Electronic gauges are also easier to mount in the OEM instrument cluster since you don't need to drill a hole in the rear of the cluster for the hard-line.
See "95'MSM boost gauge mod" - https://forum.miata.net/vb/showthread.php?t=623680&highlight=boost+gauge
Regarding the coolant re-route: Supermiata Qmax Coolant Reroute is "the new hotness" and it's much easier to fit
See https://www.miataturbo.net/engine-performance-56/supermiata-qmax-coolant-reroute-94127/
You should also be doing lots of research on MT, its the best place for information on MX5 turbo builds (just be sure to search first before asking to be be spoon fed otherwise you'll get e-gang-raped; include as much relevant information as you can and mention what you've already investigated so that it's obvious that you've actually put some effort into the query).
As coolie said, "Don't cheap on fittings, endless oil weeping is very frustrating." - spend the money on SpeedFlow or AeroFlow fittings and never worry about them again. I've seen some really nice eBay billett aluminium oil filter relocation blocks but their fittings were absolute crap (despite being aluminium, they even felt too light compared to SpeedFLow and AeroFlow fittings and looked brittle).
For hose lines, stainless steel looks great but they're not very flexible which makes routing more difficult and you MUST ensure that they do NOT contact anything because their vibrations will cause them to saw into anything they come into contact with - use them for simple runs only.
I found SpeedFlow teflon hoses to be more flexible than the AeroFlow hoses which I reaaly needed for my Oil Cooler and Relocation Block installation.
Regarding the intercooler plumbing:
I need to re-do my hotside plumbing when I can afford to install the TSE manifold but the coldside I'm happy with.
Originally I bought an eBay intercooler kit which included a bunch of 2.5" aluminium pipes and cheap/crappy silicone couplers and worm clamps - I ended up only using a J-pipe and a short 90* pipe and none of the cheap/nasty couplers or worm-clamps (the worm clamps didn't have rounded edges so bite into the hose). I wasn't happy with this and subsequently bought the FM silicone cold-side hose to upgrade "The Cobra", cutting the hose in two places below and eliminating the short 90* pipe and coupler and hose clamp:
For details see:
http://mx5cartalk.com/forum/viewtopic.php?f=57&t=41091&start=101
http://mx5cartalk.com/forum/viewtopic.php?f=57&t=41091&start=129
and that could strike fear 
