Need a 4.3 V-6 For a tired ECSB 89 Chevy PU With TBI

I am not sure if the newer SFI 4.3s will work if i just swap intakes and accesories
are the Heads Diffrent?

My freind's 16 year old got ahold of his Work truck,Got it stuck,Smoked the Clutch and Then Blew Engine!
It Knocks, it smokes, and the oil looks like a milkshake, i think its done.

Please PM me if you got one laying around In Texas

Thanks