Thank you gentlemen.
I figured its probably the same surname, just a variation of the spelling.

My 6th great-grandfather (John Scoby) had his surname spelled 3 different ways in his own lifetime: Scoby, Scobie, Scobee.
It sure makes genealogy an adventure at times!

So, does anybody out there have any background on the McIlstalker /MacInstalker family? I'm kind of curious.

Thanks again!