yes you can do it yourself rul of thumb $500 to do it properly top end only. Cylinder will need bored, new pistion kit, your machine is nearly 20 years old so none of your crank bearings or rod bearings will be tight or in spec anymore. I did my entire motor in my 88 for the following costs.
Bore cylinder, put in new rod and bushings, true crank and new crank bearings and fly cut base of cylinder to raise compressions, all OEM gaskets and some new seals, rebuild a head and new cam chain. Nothing was in spec anymore and most of the critical bearings moved, the rod moved up and down also but the machine ran fine. I had a cam chain that was badly stretched so with this years down time I dug into it.
I have a shop do the machine work, I do the assembly and disassembly of the motor. $800.00
