Question about flexplate (302)

[deemac]

Hey guys, i am switching the motor in my ranger from an older 302(i dont know what year because it came in the truck when i bought it) to a 93 5.0 HO from a mustang gt. I am running a c4 trans. The engine i took out of my truck has a flexplate and torque converter that are a smaller diameter than the ones that came on the mustang emgine and trans(i want to use my c4 because its a 4x4 and i already have the advance adaptors tail housing and stuff installed and i left the transmission in the truck). I was reading that sometime in the 80's ford switched to a heavier flexplate and harmonic balancer and you have to use them or your engine will not be balanced. Is my smaller flexplate that was on my truck the lighter one? Can i use it on my HO 5.0? I have a bigger torque convertor and bellhousing that can go on my c4 that i think will probably bolt onto the HO 5.0's flexplate...but they are a little bit thicker too which causes a clearance issue with my water pump and radiator. I could use them and move my transmission and everything back about an inch...but if i dont have to it would be nicer. So my question is:

-can i use the smaller flexplate and torque convertor?
-Is there a way of identifying whether the smaller flexplate is the lighter one i read about?

thanks guys for any help or advice you can give me.

 

[alaskan155]

28oz for 81 or 82 and older(289s, 302, 315w(all years) and 50oz for new 302. easy way to tell year is look by the starter for casting numbers on the block and post back,(have to remove starter

p.s. if it starts with E(80) and a number greater than 2 you should be good, C (60) and or D(70) bad 28oz,

2-piece rear main seal and 3-bolt harmonic balancer is also a 280z

crank casting

Crank I.D. Nos. (302) should reflect these Casting I.D. Nos.-

2M-2MA-2MAD 28 OZ. 68/80

2MAE 50 OZ. 81/