New Supra...lots of little problems.

[TxSpeedBoy]

As far as I can tell, the coolant system is full. I put water in the radiator and it seemed to help a little and no over flow. But it seems to happen more rapidly when I just get off of the highway. No sounds from the dash though. I will try and get a block test and compression check done. Sorry about the seemingly dumb questions, I am new to this to a certain extent. I have spent alot of time reading and planning, but have never gotten the opportunity to actualy do this. This car needs alot to get it running right...then comes the aftermarket. Just a quick question though, Would it be better to go with OEM parts for now until it is strong enough to handle the aftermarket or should I just go ahead with the aftermarket replacements? Or would just vary from part to part? Aslo, I think I do have a blown head gasket, I there is oil in around the spark plugs...the plug that sits infront of the other 5, there is oil in there. Any ideas on how much it might be to replace all seals and gaskets...I am sure that after 167000 miles the car needs it.

Thanks so much for your help so far. Glad to finally find a forum that's not full of people talking crap about everyone else.