First, that is a mis-use of the autonumber capability. IF you actually need numbering to be contiguous AND it has to be that way after a record gets deleted, you are doing something that Access won't do for you. You will have to code this up for yourself. An autonumber is an internal feature of Access (and most other DB's have a similar ability) to give you a unique - but not actually predictable - record identifier. If you are changing PKs in a database that has relationships based on those PKs then they should not have been PKs in the first place. A PK is, by most definitions, a value that does not change for the lifetime of the record, used solely to identify the record, and having NO OTHER MEANING.
If you are doing this for some fiduciary requirement or some other business issue, there are ways to generate a "temporary local" sequence number that would look like the same thing as you are requesting - but the real PK would still be the autonumbers with gaps as they occur. Further, if you have inter-table relationships (and you said you did) then you are looking at a massive set of queries for something that is cosmetic in nature.
It is, of course, your DB, so we have to take at face value that you think you want this. However, from the comments you are getting, I think you can see that we have a problem with the request. So let's do this another way. WHY do you think you need this? What is the business reason? Or it is really just a matter of cosmetics?