351w gear drive trouble

I have an edelbrock accu drive timing gear drive I want to put in a 351w rebuild. My engine guy had me stop over today to look at the build. The instructions say to shave the axle down on the large idler gear to get clearance to the block. My idler gears stick out 3/8 inch!. Thats more than a shave - plus if we did that the axle on the small gear would also need cutting for clearance. Are there different 351w blocks? Different gear axles? I cant believe it was ment to cut that much off. Any ideas?

 

Edelbrock tech line may help.

 

I'll try them Monday. I like the real world advice given here is why I posted. thanks