Inline 6 Engine problems...

I have a 1983 Ford f-150 with a '93 fuel injected converted to carb, straight six engine. 4.9L, one barrel carb, 4 speed manual tranny with overdrive, and the engine is causing major blowby. oil is literally getting everywhere and i need to know what i should do to get the problem fixed. do i need to have it overhauled or do i need my heads to be redone or what? this has been happening for a while and its time to see what i need to do. i do use Valvoline 10w40 oil not synthetic. please any insight would be real helpful and appreciated! thanks.:eek: