Connecting trickle charger lead to twin batteries?

[911hillclimber]

Going to fit a permanent trickle charger lead to the 73 911T I have.

It uses twin 12V batteries as factory fit.

For the lead of the charger, do I connect the red lead to the rhs + ve battery post and the black lead to the earth stud on the shell which the lhs battery - ve lead bolts to?

No fitting instructions provided, hence this question, i want to be sure i can charge/condition the two batteries simultaneously.

Thanks in advance.

[hot66]

I’ve got mine connected to one battery only

[inaglasshouse]

They are wired in the simplest possible parallel scheme. Positive terminals of each battery are directly connected together. Negatives to vehicle earth of course.

Therefore it makes no difference where you connect. If you connect both leads to one battery, you are charging both (in parallel).

[911hillclimber]

Thank you both, will follow the advice!