If you replaced the engine because it "blew", it's quite possible you cooked some wires due to overheating, so I suspect your problem is electrical.

Check the wires and the battery. If it won't start when warm it's a sign the cables, connections or the battery are fried fried. Just clean teh battery connections first then put all lights on and check whether they dim (turn yellow) or not. If they dim, the problenm is the battery (no charge). Check battery fluids and recharge as necessary then check again. Fully cahrged it shoudl start teh car no problem at all. Heck if you don't know, simply replace the battery and try again.

Thn check the alternator wire, it's quite susceptible to frying in this car, and will cause teh abttery to failin short order.

Lack of electricity will make the ligts dim, the relays buzz and the coil put out insufficient spark under high demand.

HTH...