Your not going to benefit much if any by using a tb larger than 65mm. A few people run the e303 or b303 cam and love it but I would go to camquest and see what can specs it gives. You should be able to pick one similar to the specs it gives.
i havent personally done that intake, but i have done others. i usually gasket match and smooth the casting flash.
what you want to do is put the gasket on the intake. put a few bolts in so the intake is aligned. then use a scribe or scratching tool to trace the inside of the gasket. then using a dremal tool open it up to the lines. then use a finer bit or flapper etc on the inside and smooth put all the casting flash. also radius any sharp corners and knock down any high spots.
summit racing and jegs sell kits to use with dremals and die grinders that will have everything you need to do it really nice. you can also search youtube and find some good how to videos.
Cool. Good luck.
Btw if its the tubular intake, I don't think you can take go very far with it. But you can definitely still smooth the casting flash.
Also check in the useful info sticky thread. Maybe under tmoss ?
What exactly is the purpose of the pintle caps on the bottom of the injectors? I did gt40 swap an now its missing like crazy i noticed some of them were cracked didnt replace i plan on it just none of the parts stires had them instock plan on just gettin new injectors