Re: Is there a go-to thread for what you'll need for a build?
I'm not a four stroke guy so I cannot comment on which kit to buy, but I've been building mtb's for several years now and I can certainly help choose a good bike to build on.
Look for a higher end bike like a trek, felt, specialized, diamondback (older models) etc.
Your should look for a steel frame with good brakes, V-brakes at minimum, disc if you can afford a tophat adapter for the drive sproket (very good setup) You want alloy rims and good quality aluminum hubs, and comfortable riding position for YOU. Sit on several or test ride a few styles at a local bike shop to decide what you like. (I am older and prefer a more upright position to ease my back.) A good thick quality seat is mandatory on a mtb because you sit more.
Oversized or oval tubing can be a pain to deal with as well so look for more conventional designs when shopping.
Just a few tips I go by when looking for a build bike.
The type of bike depends on what kind of rider you are. Cruisers are comfortable and good looking but don't handle as well as mountain bikes. Mountain bike frames are usually stronger and easier to mount an engine on due to straight tubes and lots of room. The chain line is about as easy to setup on either style, but mountain bikes usually have better brakes.
I would suggest getting your engine kit first and use the mount to help you choose a frame. You can take it with you and test fit it in any frame you see to give you some idea of what will work.
The main issue doing this is having to look at the engine until you get a bike!
If more is better, then too much is just enough.
If you can't afford it, build it yourself.