i picked up a poorly made manifold from the 90's for 120 shipped or something like that. and got mine efi'd for about $450.
given, this was just to see how cheap i could get it done for, and it is very low quality.
but yeah megasquirt works, but you get what you pay for as with anything. The more expensive megasquirts are better, along with pricier intake manifolds.
for the 3tc, just use the generic kit and make your own harness and everything.