Not too sure if they are similar, but I have an e60 I tried. 4 in, 6 out seemed to work fine for that one. Just try different ones. 5 in, 6 out seemed ok, but gave a high idle.
I got my e60 from an Infiniti j30 at the local junkyard. I got it because in the sticky maf thread, it said it was supposed to support 500hp. However, I've found out different. It's 350hp. Same as a maxima maf.
I've been trying to find one that actually supports around 500hp.
e60 is the same as an n60 they both support 325whp, however its wierd that you got your e60 out off a J30 e60's came on I30 J30 came with N62 maf same as a 300ZX
^^That's what I thought. It was a 93 j30. But, the maf has a pink label. And I read from a couple of places that the n62 has a yellow label, and the e60 has pink.
I did find this reference to the p60 though...
"P60 has less resolution than the N62 and is therefore slightly less desireable when trying to mess with a tune in Nistune for example."
The P60 is the Q45 MAF and has less resolution than the Z32 MAF. The Z32 is good for a lot of power, most than what people usually go for, so its better suited to the SR20.