Have a good read of this http://www.megamanual.com/ms2/tune.htm

You will want high impedance injectors, VXR injectors can be bought cheaply (sub £100).

Mapping is easy to pick up your self, mapping things safely takes a little practice (but is perfectly learn-able), its really an experience thing, you won't screw the last 10% out of your car that a good tuner with a dyno would, but with some learning you will have a good safe car thats nice to drive.

There are more and more tuners/individuals who are feeling happier about tuning megasquirt these days too, so depending on what other tuners are close to you that may also be an option.

Maybe your tuner would be okay with you picking up a 2nd hand omex which you could fit before giving him the car? Any good tuner would be able to map MS though tbh, they just don't like fixing the millions of fuck ups that badly built ones normally have...

Rob,