Inside custom model __init__, you can define these params* as instances of nn.Parameter and use it in your computation (new model’s forward) along with freezed weights from your earlier model.
Use optimizer to optimize new_model.parameters(). Will this work for you?
But remember that you can’t reassign params* in any case. You can use them in computation as nn.Parameter. Optimizer will take care of updating the `params* with its gradients automatically.