I insured my C-60 through Progressive,and they didn't even flinch. It didn't cost me any more than it did for my '62 one ton. I told them I didn't use it to haul for anybody,just my own stuff,and then rarely. (truth)
Speed

1954 GMC 350
1957 GMC 1/2 ton
1962 Chevy C-30
1952 Chevy 6400 dump bed project truck
'98 Harley FLSTC
'66 Pontiac Catalina
'76 Chevy 1 ton Duallie
'84 Bronco II
'78 Dodge W-200
'81 Toyota 4X4 truck