I am in Virginia, and ended up registering it in Vermont as a motorhome. If Virginia ever says I have to get a Virginia registration, then at least it is already a "motorhome" and I will not have to proof anything, just transfer it. Look up Vermont title on this forum.
If you are going to leave the seats in and not convert it then option 2 is you better bet.
Do not title as a truck you as will have to go into weigh stations, and they can set up kangaroo court on you then....