Quite a bit of info here, maybe this will help.

http://www.therangerstation.com/forums/showthread.php?t=124928

i robbed a roller cam from an engine once and if i ammember correctly it had dual spark plugs ,..is that typical of rangers ?

It depends on the year and I am not 100% sure when they changed.  I want to say 93 but don't quote me on it.  I knew a person that ran the dual head plug in his car but only used the one row of spark plugs.  The other end was just plugged.  He said it ran normal?

Yes it would run fine, however the Roller Cam head that you need is a single plug head and that is the one you want because the CAM journals are a different size on the 8 plug head. So you can not swap them with out using the head. Check with Turboford.org for more info.

This is not true I have a roller cam out of a 90 ranger that has the 8 plug head in my turbo bobcat. The head is completely different in the fact you cant use a pinto intake on it but the cam its self is the same and can be swapped directly into a pinto head you just need the roller followers to go with it.
As for the smaller journal thing that's in the block the 8 plug engines have small crank journals hence the reason you can put in a 2.5 crank without the spacers in one.