Will 7.5" axle fit on 8.8"?

[Fox Body]

2 questions:

See, just got 3.55s installed and I need a new right axle (the one I have is slightly bent). The one I have isn't all that bad, but it would do good to get me another within the next month or two.
I was told by a pretty reliable source that the 7.5" axle would not fit in the 8.8", but then another more reliable source (?) told me that it would fit b/c they are the same axles. I have a 7.5" at home and would like to use it (save $$), but ..... Can I use a right axle from 7.5" rear?

Also, a friend told me that he has an axle from an 8.8, but he doesn't know which side it's from. Now I would assume that you would have to have the same side, right? Would I be able to use an axle from an 8.8" rear if it were a left axle?

"because, no one’s really gonna be free until nerd persecution ends." ---Revenge of the Nerds

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'79 Mustang Coup
4" Cowl
Weld wheels (15x6;15x8)
Stock 5.8L
C4 w/ shift kit
1.5" MAC full length headers
Holley 750 CFM
Edelbrock intake
2.5" Off road H-pipe, 2-chamber Flowmasters
8.8" Rear end w/ 3.55s (Now that's more like it!)
Front: 225/60/15 Rear: 255/60/15 Eagle GT II
14 x 4" K&N air filter (getting the Xtreme setup soon)