That is indeed the hole for the original coil mount. This shouldn't be an issue, but it may indicate that some other things may not be done as originally designed and intended.
Get yourself a bentley manual as soon as possible. It is the definitive answer to the multitude of questions you will inevitably have, and will help you sort through any differences in your bus and the oe layout. Also start cruising on the samba baywindow forum. Welcome to the club!
I used this one by Hella. It fits the opening almost perfectly. I think we welded a small tab to mount it. No more rolling fuses to troubleshoot. https://www.amazon.com/gp/product/B000VU9D20/ref=ppx\_yo\_dt\_b\_search\_asin\_title?ie=UTF8&psc=1
The official service manual and the idiot book are absolutely invaluable for a new VW owner.
Volkswagen Station Wagon, Bus (Type 2) Service Manual: 1968, 1969, 1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979 (Volkswagen Service Manuals) https://www.amazon.com/dp/0837616352/ref=cm_sw_r_cp_api_glt_fabc_TCFQ0ECESJ72XVBNXZPM
How to Keep Your Volkswagen Alive: A Manual of Step-by-Step Procedures for the Compleat Idiot https://www.amazon.com/dp/1566913101/ref=cm_sw_r_cp_api_glt_fabc_JYE20AS6VN3B3KYCRVCV
For an extra special gift look for an early printing of the idiot book on eBay. ( just make sure to get one after ‘69!
There are other books, but this one helped me tremendously. And if it's on your shelf, people will know you're a serious VW guy. Haha.
https://www.amazon.com/dp/1566913101/ref=cm_sw_r_cp_awdb_imm_GR35A5DRQ61VDJN46XDF
I got the Bug one from Amazon. I bought the red one at AutoZone. But I've already ordered two green keychains for the bus. Can't wait for them to arrive! Amazing quality.
This will plug into the factory receptacle in the dash and provide sufficient power to keep a blue tooth speaker and a phone charged and operating. The speakers I wired in 23 years ago are shot and this is how I have music these days.
https://www.amazon.com/gp/product/B075J7DZMW/ref=ox_sc_saved_title_5?smid=AXLVUUCJK6134&psc=1
Congrats! please do your self a favor and buy this. Great 0-60 and actually one of the most humorous things I've ever read.
Also join www.thesamba.com great community there and a ton of helpful people, along with ideas and such. Of note, it is about as troll'y as reddit.
Texas is home of a few VW clubs, find them, use them, join them. Hahah, but seriously those guys will know the good shops and will have a shitton of connections. Also a bunch of them probably horde parts.
Your bus has a name, you will figure it out as you travel with it. Give it time the name will become apparent. For example Phoenix [my wife's and my bus] has risen from the smoldering ashes a couple of times now.
Honestly if you have any questions at all don't hesitate to pm me as well, always happy to help a new member.