Something that I forgot to mention, although I am sure you would get great results with the G776-XX (XX being the Listed size of the Mill, in Inches) Try to get a G778-xx series mill, the 778 series mills have the upgraded CNC end brackets, rather than the Cast end Brackets of the 776 series, all the parts are interchangeable between the 776 and the 778, the 776 is NLA, replaced by the 778, but you may find some NOS 776 somewhere, at least Know what you are ordering. If you do order a NOS 776, at least compare prices, and make sure that you are getting a decent discount on the 776. The 776 is still a Great mill, but the 778 is More Desirable
You can order "Handle and Rail" sets to make your Mill different lengths if you want, if you buy a 36", and end up needing a 48" or larger, you can order the handle and rail sets up to I believe 84", in 12" increments from 36" on up. over 48", it is advisable to add another end bracket to the middle of the mill, to help stiffen up the longer mill. Granberg has virtually every part available, as well as some add ons too, their Customer Service has been Great to deal with.
I really Like their "EZ Rails" system for guiding the mill, you Really only need a Guide system for the first cut, but I use it for every cut, maybe with practice, I would get better, but I was getting "Bar Dive" beginning and ending my cuts without it. You may do better than me.
The Granberg EZ Rails are made out of the same material, as the frame rails, so if buy a 5' set, it can be converted to a 60" mill by swapping the EZ Rail hardware to the Mill Hardware from your existing mill.
I ordered most of my milling gear from Power Equipment Direct, on ebay, their current prices are
G778-24 $199.99/Free Shipping
G778-30 $219.99/Free Shipping
G778-36 $229.99/Free Shipping
G778-48 $249.99/Free Shipping
G777 $159.99/ $33.53 Shipping
Small Log Mill
G555-B $$129.99/ $24.82 Shipping
The G777 Small Log Mill is similar to the G778 series, but only clamps at the thrust end, and not the bar end, and is only intended for bars up to 20"
The G555-B Edging Mill, formerly known as the "Mini Mill" is used mainly for edging cants, works very well, especially after the first cut is made with the main mill, giving a flat surface to work with
If ordering the G777 or G555-B with a larger mill, it should ship Free as well,
Enjoy, and stay SAFE, and HEALTHY
Doug