Shortly after I purchased a 1973 911E Targa the ‘73 gas shortage hit the US. I had Stoddard install a 110 liter tank. It has been great with noticeable handling improvement when tank is full (29 gallons). Have always thought I should secure the spare tire but never have. Spare is a collapsible tire on an original 15x6 cookie cutter. Wondering about possible options to secure it. Advice appreciated. Thanks!