Packer to STP conversion

[ChrisCW]

Hey! I just came out and have finally begun to be myself and live as a man. Anyway, I am new to all of this but I recently purchased a Masho packer and a Doc Johnson Pack it (lite). I was wondering if anybody has had any luck converting either of those packers into an STP. If not, what type of packer (the cheaper the better) would you recommend for a stp conversion.

Also, has anyone tried using a nipple (from a baby bottle) instead of a medicine spoon as the top part of the Stp tubing. I feel like a medicine spoon would be too small for me to
Use comfortably and confidently.