Is a GMC truck just a dressed up Chevy truck?

GMC dealers are or were truck people. They sell heavier duty commercial trucks, fleets/ utilities/ many bought GMC trucks
I came close to buying a K30 from a GMC dealer, they knew their product and offered a better deal and service
I cant comment on the trim issues as I wouldn't know
The GM 350 four bolt main engine with the SM465 4 speed was virtually indestructible. Their automatic trans also held up very well