2nd Gen OMP differences?
 

I understand from looking at the Mazdatrix web site that there are two different 2nd gen OMP pumps:

The 84-88 13B Six Port/non-turbo part# 14-6000-N246 and
the 86-88 13B Turbo part# 14-6000-N318

Can someone tell me what the difference is in these pumps? Are they interchangable as far as the front cover mounting ?