You could try using a pair of jumper cables as temporary positive and negative cables. helped me once when I lost a ground from a corroded cable inside the insulation

 

Since I have a 95 12 valve I was interested in this thread in case it ever happens to me. So some stranger with only 5 posts chimes in with a problem and this place dives in head first to help!!! The people in this forum are the best. Just sayin

 

Go with Richard's suggestion (use jumper cables as a temporary replacement for your battery cables) to eliminate the cables as a problem.

If that doesn't solve it take a look at the contacts in the starter solenoid. They have a reputation of corroding. I was able to find an old-time mechanic in town who had a supply of them for Chrysler/Dodge starters. Solved the slow cranking problem on my truck.