If the snapper is the end man on the line of scrimmage and has an eligible # let's say #30, is he an eligible receiver? Can he go out for a pass?

On a regular scrimmage play yes as long as there are 5 other players on the line of scrimmage with numbers 50 thru 79.

On a scrimmage kick formation the numbering requirements do not exist.

So yes as long as you have 7 men on the line and the correct numbers coincide with the type of play this is legal.

Swinging Gate
 

You will see this formation alot in HS FB. This should be 'touched on' during the pre-game talk.

This situation comes up on the muddle huddle play on try for point plays. If the snapper is on the end of the line and has a legal receivers number, then he is an eligible receiver.

Now someone correct me if I'm having a brain fart on this. Even if A has less than seven players on the line, if the snapper is on the end of the line and is wearing an eligible number, he is eligible. Yes, they are guilty of illegal formation, but if the snapper goes downfield and touches a pass it would NOT be OPI. Am I correct or in left field on this one?

Stop the farting....
Players on the END of the line wearing the eligible numbers can catch a forward pass. In this case, the snapper just happends to be on the END of the line and wearing an eligible number.
Having less than 7 on the line does not change the eligibility of those on the END of the line given they are wearing the numbers 1-49 or 80-99.

No more beans for my brain (or something like that...??). I was 99.9% sure I was correct, but for some unknown reason, what I said just didn't sound right. Anyway, thanks for the confirmation.