Thermostat doesn't open after hose replacement

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I just put all new radiator hoses on my Spider and a new overflow bottle. My new thermostat (from Vicks last summer) which has previously given me no problems seems to not be opening. The reason I believe this is the the fan doesn’t turn on and the engine overheats pretty quickly. I forced the fan to blow and then noticed the lower radiator and hose are cold...this happened after running the fan but I still think it's the issue.

I re-drained coolant and re-filled today with the front elevated, then part way through lowered the car flat and did the second half according to Ernest Build’s method, filling up the rear coolant hose above the head, which succeeded last time. But with no improvement. I guess there may be an air bubble still stuck under my thermostat…blindly guessing this detail since I’ve read something about it.

The only differences I made to the system when I reinstalled are: I coated the thermostat with simichrome polish on the outside to shine it up and a lick of vaseline at the hose attachments for easier removal next time. I've read simichrome is heat resistant but the heat is coming from the inside so I don't see this as a risk.

I left the hose coils inside the new hoses, which the previous owner had installed for stiffness. I think I solved his problem since I too was having hoses collapse...I discovered the narrow hose from radiator cap to overflow bottle was undersized. If I removed these hose coils it would be a lot easier to massage the air out of the hoses.

Hoping this is a common issue.