Wondering if possible to retrofit an older gas furnace with a 2 stage variable speed motor to save electricity. This is an old furnace with an 8 amp motor. The furnace is old but in great shape would just be interested in saving on the electric bills which double in winter to turn the blower. The lights dim when this thing kicks in.

Any thoughts? Recommendations on sites where I might be able to purchase motor and needed electronics would be appreciated.

Regards!