Why not? From the .pdf posted above, it states you have to reserve before install. No one has been able to clarify 'self installation' vs going to a shop, but I wouldn't count yourself out just yet...
Program Steps & Timeline
The program will include the following steps and timeline:
[1] Decide: The Owner arranges for purchase and schedules installation of TSO-certified avionics for an
Eligible Aircraft.
[2] Reserve: Before avionics installation occurs, the Aircraft Owner must submit a Rebate Reservation
via a website. Upon successful submission, an email will be sent to the submitter with a Rebate
Reservation Code. During the rebate reservation process, the Eligible Aircraft’s information is validated
against the Civil Aircraft Registry (CAR), including ownership information. If there are discrepancies,
the Aircraft Owner may continue with the reservation process; but before a valid Incentive Code can be
obtained in step [5], the Aircraft Owner must insure that the CAR data for their Eligible Aircraft is
corrected. See Notes A and B.
NOTE: The CAR is updated weekly, typically the first business day of the week; any updates to the
CAR in a given week will typically not be available until the following week.
[3] Install: TSO-certified ADS-B avionics are installed in the Eligible Aircraft.
[4] Fly & Validate: Only after the prior steps are completed, the Eligible Aircraft is flown in the airspace
defined in 14 CFR §91.225 (see Note C for an exception to this) for at least 30 minutes, with at least 10
aggregate minutes of maneuvering flight, per the guidance in AC 20-165B After flight, a PCR and GAIRS
report is obtained to validate performance of the Eligible Aircraft’s ADS-B installation. Note that it may
be necessary to repeat this step more than once, until the GAIRS report indicates PASS for all fields and
provides an Incentive Code in the Rebate Status section.
[5] Claim: Within 60 days of the scheduled installation date, the Aircraft Owner gathers their Rebate
Reservation Code (from step [2]) and their Incentive Code (from step [4]) and navigates to the ADS-B
Rebate website to claim their rebate. After FAA validates a Rebate Claim, the rebate check will be mailed
to the Aircraft Owner as listed in the FAA Civil Aircraft Registry. Only one Rebate Claim per Aircraft
Owner will be paid.