i just recent bought a 95 eclipse rs. it has 210,000 miles and although running smooth i want to get a new or rebuilt jdm dropin engine.  what engine is the best for this and what is involved.  i notice that all the ones i see online are setup backwards from what i have so i know the trans has to change too.  would it just be better to build what ive got.  any suggestions appreciated.  

Some times it is. First you have to ask your self... "How much do I want spend?"... Money is an issue, especially with the economy is the way it is. Rebuilding is an affordable option, just see how much beefing up you can do with aftermarket stuff so you can bolt on a turbo. It's cheaper than getting a whole new platform to stick in your ride. For the money... turbo all the way.  

thanx for the advise.  i am leaning more towards a good rebuild of the engine that i have. i am not looking to turbo it yet but am looking to make sure it can handle whatever turbo i decide to put on it later.  right now just get a good 200-250 out of just engine any suggestions on parts and specs.
i also have this issue where the cars engine will shut down and restart after a second or so.  when this happens its looses tachs signal but nothing else i.e. radio, speedo, lights or anything else are affected. anyone know what this is.  it is not fuel related it is electrical. anyone with this issue please help.  

If you plan on installing a turbo later, you're better off just building it to suite the need now so that you don't have extra headaches when you start building. As far as parts go, you have to be on good speaking terms with your machinist so that he knows exactly what your plans and goals are. Any one on this site can give you a serious parts list of goodies to install but, innevitably, it's going to end up being a descision that you and the machinist will have to make together, in the end.
Your problem with the sudden stop sounds like an intermitent issue with the crank sensor. Check the connector to it and any other connectors in that cicuit and if it's good then you should hook up a scanner and see what it's doing, as you drive, when it happens. You definately need a partner for this task. It could be another such sensor but that is what it sounds like to me. With out being there, it is hard to determine.
I want to give you more areas of electronic interest to check but I have a severe thunderstorm warning for my area and it sounds as if it's getting closer, as I write. Lightning and computers don't get along too well!